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					Riza Ridho Apt


                 1
2
         Classification of
     Ischemic Heart Disease

     Ischemic Heart Disease



Chronic coronary      Acute coronary
  artery disease         syndromes
 (stable angina)
                     -Unstable Angina
                     -Myocardial infarction



                                              3
   1) Drugs that Affect Blood Coagulation


• Used in the prevention and management of thrombotic and
  thromboembolic disorders




                                                            4
Intrinsic System                                     =Factor affected by oral anticoagulatants
                                                     (Vitamin K-dependent clotting factor)
XII
            XIIa                                    =Factor affected by heparin
                                                    (factor that can be inactivated by antithrombin)

       XI                             Extrinsic System (thromboplastin)
                   XIa


            IX                       VIIa          VII
                         IXa



                    X           Xa          X



                 PROTHROMBIN          THROMBIN


                               FIBRINOGEN       FIBRIN (monomer)


                                                FIBRIN (polymer)                              5
      THE COAGULATION CASCADE
  1) Drugs that Affect Blood Coagulation (Cont’d)

• (i) Anticoagulant drugs
  – Drugs that disrupt the coagulation cascade, &
    thereby suppress production of fibrin
  – Prevention of thrombosis in veins
  – Heparin
     • Suppresses coagulation by helping antithrombin III
       inactivate thrombin, factor Xa and other clotting factors
     • Used in:
        – Prevention and treatment of pulmonary embolism, stroke,
          deep vein thrombosis (DVT)
        – Prevent coagulation in devices in open heart surgery and
          renal dialysis
        – Treatment of disseminated intravascular coagulation
        – Adjunct to thrombolytic therapy of acute myocardial
          infarction
                                                                     6
1) Drugs that Affect Blood Coagulation (Cont’d)

 • Dosage
    – Based on body weights of the patients & their
      indications

 • Adverse effects
    – Hemorrhage
    – Thrombocytopenia
        » Decrease platelet count
    – Hypersensitivity reactions
        » Since commercial heparin is extracted from
          animal tissue


                                                       7
1) Drugs that Affect Blood Coagulation (Cont’d)


– Warfarin
   • Suppress coagulation by acting as an antagonist of
     vitamin K
   • 4 clotting factors (VII, IX, X & prothrombin) require
     vitamin K for their synthesis
   • Indications:
       – Prevention of venous thrombosis & associated
         pulmonary embolism
       – prevention of thromboembolism in patients with
         prosthetic heart valves
       – Prevention of thrombosis during atrial fibrillation
       – Reduce risk of recurrent transient ischemic
         attacks (TIAs) & recurrent MI
                                                               8
1) Drugs that Affect Blood Coagulation (Cont’d)

      • Daily dose
         – usually 3 to 9 mg but it should be based on the INR
            values.
         – INR targeted values are different in different
            indications, usually within 2 to 3.5

      • Adverse effects:
         – Hemorrhage
         – Teratogenic




                                                                 9
1) Drugs that Affect Blood Coagulation (Cont’d)
      • (ii) Antiplatelet drugs
         – Suppress platelet aggregation
         – Indicated for prevention of thrombosis in arteries




                                                            10
Platelet Adhesion
11) Drugs that Affect Blood Coagulation (Cont’d)


 • Clopidogrel (Plavix)
     – Adenosine diphosphate receptor (ADP) antagonist
     – Irreversible blocking of ADP receptors on the
       platelet surface
     – Prevent ADP-stimulated aggregation
     – Indicated for prevention of stroke, vascular death
       & MI
     – The combination of aspirin and clopidogrel appears
       to be the most effective and safest therapy for
       secondary prevention of stroke.



                                                            12
11) Drugs that Affect Blood Coagulation (Cont’d)


 • Clopidogrel (Plavix)

     – Dose
        » 75 mg po daily with or without food

     – Adverse effects:
        » Hemorrhage (GI & Intracranial)
        » GI side effects




                                                   13
1) Drugs that Affect Blood Coagulation (Cont’d)

            • Aspirin
               – Suppress platelet aggregation by causing
                 irreversible inhibition of cyclooxygenase, an
                 enzyme required by platelets to synthesize
                 thromboxane A2 (TXA2)




                                                             14
1) Drugs that Affect Blood Coagulation (Cont’d)


      • Aspirin
         – Indicated in :
              » Primary prophylaxsis of MI
              » Prevention of reinfarction patients who have
                experienced an acute MI
              » Prevention of stroke in patients with a history
                of TIAs
         – Dose
            » Maintenance treatment 75-150 mg daily po
         – Adverse effects
            » GI hemorrhage & also other hemorrhage
            » Bronchospasm
                                                                  15
1) Drugs that Affect Blood Coagulation (Cont’d)


• (iii) Thrombolytic drugs
   – Promote lysis of fibrin, thereby cause dissolution of
       thrombi
         • Streptokinase
            – First bind to plasminogen to form an active
              complex
            – The streptokinase-plasminogen complex then
              catalyzes the conversion of other plasminogen
              molecules into plasmin, an enzyme that digests
              the fibrin meshwork of clots



                                                               16
1) Drugs that Affect Blood Coagulation (Cont’d)

      • Alteplase (tPA)
          – Also known as tissue plasminogen activator (tPA)
          – Is produced commercially by recombinant DNA
            technology
          – Human tPA is an enzyme that promotes
            conversion of plasminogen to plasmin, an enzyme
            that digests the fibrin matrix of clots

      • Adverse effects:
         – Nausea & vomiting
         – Bleeding


                                                               17
1) Drugs that Affect Blood Coagulation (Cont’d)
    • Nursing Alerts:
       – Monitor signs of hemorrhage
          • Lowering of blood pressure, elevation of heart
            rate, discoloration of urine or stools, bruises,
            petechiae, etc.
       – Monitor INR, APTT, PT regularly
       – Warfarin is contraindicated in pregnancy & breast-
         feeding




                                                           18
    2) Cardiotonics & other
         Inotropic Drugs
• The cardiotonics are drugs used to increase the
  efficiency & improve the contraction of the heart
  muscle, which leads to improved blood flow to all
  tissues of the body




                                                      19
   2) Cardiotonics & other
     Inotropic Drugs (Cont’d)
• Digoxin
  – Inhibits the enzyme Na, K-adenosine
    triphosphatase (Na, K-ATPase), increases
    the movement of Na out of myocardial
    cells after contraction
  – As a result, Ca enters the cell in exchange
    for Na, causing additional Ca to be
    released from intracellular binding sites
  – With the increase in intracellular
    concentration of free Ca ions, more Ca is
    available to activate the contractile
    proteins, actin & myosin, & increase
    myocardial contractility
                                              20
        2) Cardiotonics & other
          Inotropic Drugs (Cont’d)
• Side effects:
   – Usually associated with excessive dose
   – Digoxin toxicity:
      • anorexia, nausea, vomiting, diarrhoea, visual
        disturbance, confusion & mental disturbance,
        arrthythmia, heart block
• Dosage:
   – Maintenance: 62.5-500 mcg daily




                                                        21
        2) Cardiotonics & other
          Inotropic Drugs (Cont’d)
• Milrinone (Primacor)
   – Increase levels of cyclic adenosine
     monophosphate (cAMP) in myocardial cells
     by inhibiting phosphodiesterase (PDE)
   – Relax vascular smooth muscle to produce
     vasodilation & decrease preload &
     afterload
   – Used in short term management of acute
     severe heart failure that is not controlled
     by digoxin, diuretics & vasodilators


                                                   22
2) Cardiotonics & other Inotropic
         Drugs (Cont’d)
• Side effects:
  – Arrhythmias, headache, hypotension


• Dosage:
  – Maximum dose: 1.13mg/kg daily




                                         23
     2) Cardiotonics & other
    Inotropic Drugs (Cont’d)
• Nursing Alerts:
  – Withhold the drug & contact the physician
    if there are any signs of digoxin toxicity or
    marked changes in the pulse rate/rhythm
  – Monitor digoxin levels closely: should be
    smaller than 2 ng/ml
  – Older adults are particularly prone to
    digoxin toxicity
  – Hypokalemia makes the heart muscle more
    sensitive to digoxin, thereby increasing the
    possibility of developing digoxin toxicity


                                               24
              3) Antihypertensive
                     Drugs
– (i) Diuretics

   • Diuretics are drugs that increase renal excretion of
     water, sodium & other electrolytes, thereby increasing
     urine formation & output
   • Used in the management of heart failure, renal &
     hepatic disease, hypertension, ophthalmic surgery




                                                          25
26
3) Antihypertensive Drugs (Cont’d)

– Thiazide diuretics:
   • Decrease reabsorption of Na, water, Cl &
     bicarbonate in the distal convoluted tubule
   • Hydrocholorothiazide
       – 25-100 mg daily or BD po
   • Indapamide (Natrilix)
       – 2.5 mg/1.5mg(S.R.) daily po




                                                   27
3) Antihypertensive Drugs (Cont’d)
    – Loop Diuretics:
       • Inhibit Na & Cl reabsorption in the ascending
         loop of Henle
       • Frusemide
           – 20-80 mg daily po
       • Bumetanide (Burinex)
           – 0.5-2 mg daily po




                                                         28
3) Antihypertensive Drugs (Cont’d)
     – Potassium-Sparing Diuretics:
        • Act directly on the distal tubule to decrease
          the exchange of Na for K
            – Amiloride : 5-20 mg daily po
            – Triamterene: 100-300 mg daily in divided
              dose po
        • Spironolactone
           – Block the Na-retaining effects of
              aldosterone in the distal tubule
           – 25-200 mg daily po




                                                          29
3) Antihypertensive Drugs (Cont’d)

– Combination Products
   • Thiazide & related diuretics are available in
     numerous fixed-dose combination with non-diuretic
     antihypertensive agents & with K-sparing diuretics.
     This can increase patient compliance & prevent K
     imbalances:
       – Dyazide (Hydrochlorothiazide 25mg+Triamterene
         50mg)
       – Moduretic (Hydrochlorothiazide 50mg+Amiloride 5mg)
       – Hyzaar (Losartan 50mg+Hydrochlorothiazide 12.5mg)




                                                              30
            3) Antihypertensive Drugs (Cont’d)
Side effects     Nursing actions                          Rationale
Increase urine   Give in the early morning if ordered     Peak action will occur during waking
output           daily                                    hours & not interrupt with sleep
                 Keep a bedpan within reach. Assist to    Mainly to avoid fall
                 the bathroom anyone who is elderly,
                 weak, dizzy, or unsteady in walking

Postural         Assist the patient to get up slowly      Avoid falling
hypotension
Possibility of   Record fluid intake & output regularly   Avoid fluid volume depletion due to
dehydration                                               excessive diuresis
Hypo/Hyper-      Monitor serum potassium level (within    Avoid K depletion due to thiazide &
kalemia          3.5- 5 mEq)                              loop diuretics or avoid K
                                                          accumulation in patient taking K-
                                                          sparing diuretics
Electrolytes     Monitor K, Na, Cl, Mg & bicarbonate      Avoid electrolyte imbalance
imbalance        levels

                                                                                            31
3) Antihypertensive Drugs (Cont’d)
   • (ii) Beta Blockers
      – Block beta-1 receptors in the heart
      – Hence:
           • Reduce heart rate
           • Reduce force of contraction
           • Reduced velocity impulse conduction through
             the AV node




                                                           32
3) Antihypertensive Drugs (Cont’d)
     – Used in:
        • Hypertension
        • Angina pectoris
        • Arrhythmias
        • Myocardial Infarction
        • Heart Failure




                                     33
3) Antihypertensive Drugs (Cont’d)

 – Differ in:
    • Receptor selectivity
    • Intrinsic sympathomimetic activity (partial agonist
      activity), e.g. Oxprenolol. Pindolol, acebutolol
    • Lipid solubility
      (Atenolol, nadolol, Sotalol are the most water-
      soluble)
    • Duration of action, e.g. Esmolol




                                                            34
        3) Antihypertensive Drugs (Cont’d)
Drug          Receptors     Maintenence Dosage in Hypertension
              Blocked
Atenolol      Beta1         50mg daily po

Metoprolol    Beta1         100-200mg daily in one to two doses po
                            200-400mg daily po (Slow release)

Carvedilol    Beta1 and 2   12.5-50mg bd po

Labetolol     Beta1 and 2   100-200mg bd po with food

Propranolol   Beta1 and 2   160-320mg daily po

                                                                     35
  3) Antihypertensive Drugs
            (Cont’d)
   Receptor Subtype       Tissue                    Effects
         Alpha 1,2   Vascular smooth           Contraction
                                         muscle

Beta 1                 Heart                      Inc. Heart Rate
                                                Inc. Force of
                                                    Contraction

  Beta 2                 Smooth muscle             Relaxation




                                                             36
3) Antihypertensive Drugs (Cont’d)
  – Adverse Effects       • Nursing Alert

    •   Bradycardia         – Check blood
    •   Hypotension           pressure & pulse
    •   Brochospasms          frequently,
    •   GI disturbances       especially when
    •   Heart failure         dosage is being
    •   Fatigue               increased




                                                 37
3) Antihypertensive Drugs (Cont’d)

• (iii) Calcium Channel Blockers (CCB)
   – Drugs that prevent calcium ions from entering cells.
   – Have the greatest effect on the heart and blood
       vessels.
   – Widely used to treat hypertension, angina pectoris and
       cardiac dysrhythmias




                                                              38
             3) Antihypertensive Drugs (Cont’d)
Classification Sites of Dosage                                     Indications
               action
                                                    Hypertension   Angina   Arrhythmias   Others


Dihydropyridine

Amlodipine        Arterioles   5-10 mg daily po          Y           Y


Felodipine S.R.   Arterioles   2.5-10 mg daily po        Y


Nifedipine        Arterioles   10-30 mg tid po           Y           Y
                               10 mg bd po
                               (Adalat Retard)
                               30-60 mg daily po
                               (Adalat GITS)
Nimodipine        Arterioles   60 mg q4h for 21                                            IND
                               days


  Key: Y-Yes; IND-Ischaemic neurological deficits                                           39
            3) Antihypertensive Drugs (Cont’d)
Classification   Sites of      Normal            Indications
                 action        dosage
                                                 Hypertension   Angina   Arrhythmias


Phenylakylamines

Verapamil        Arterioles/   40-480 mg daily   Y              Y        Y
                 heart         in 2-3 divided
                               dose, depending
                               on indications
Benzothiazepines
Diltiazem        Arterioles/   30 mg tid;      Y                Y        Y
                 heart         90 mg bd (SR)
                               100-200mg daily
                               (SR)
                                                                                   40
3) Antihypertensive Drugs (Cont’d)
    – Side effects:
       • Hypotension, dizziness, weakness, peripheral
         edema, headache, heart failure, pulmonary
         edema, nausea, constipation
       • Bradycardia (Verpamil, Diltiazem)
       • Tachycardia (Nifedipdine & other
         dihydropyridines)




                                                        41
 3) Antihypertensive Drugs (Cont’d)

• Nursing Alerts:
  – The older may have a greater hypotensive
    effect after taking CCB’s than younger adults.
    The nurse must monitor them closely during
    dosage adjustments
  – Make position changes slowly to minimize
    hypotensive effects
  – Some patients may experience dizziness and
    light-headedness, especially during early
    therapy. The nurse should assist the patient
    with all ambulatory activities and instructs
    the patients to ask for help when getting out
    of bed or ambulating                             42
 3) Antihypertensive Drugs (Cont’d)

• (iv) Drug Acting on Renin-Angiotensin System
   – There are 2 families of drugs:
        • Angiotensin-converting enzyme (ACE) inhibitors
           – Block the enzyme (ACE) that normally converts
             angiotensin I to the potent vasoconstrictor
             angiotensin II
           – Decrease vasoconstriction & decrease aldosterone
             production, reducing retention of Na and water




                                                            43
*A-II is the major stimulator of aldosterone secretion
                                                         44
 3) Antihypertensive Drugs (Cont’d)

• (iv) Drug Acting on Renin-Angiotensin System
   – There are 2 families of drugs:
        • Angiotensin-converting enzyme (ACE) inhibitors
           – Block the enzyme (ACE) that normally converts
             angiotensin I to the potent vasoconstrictor
             angiotensin II
           – Decrease vasoconstriction & decrease aldosterone
             production, reducing retention of Na and water




                                                            45
3) Antihypertensive Drugs (Cont’d)

 • Used to treat hypertension, heart failure, myocardial
   infarction, and nephropathy
     – Enalapril 10-40mg/day in 1 or 2 doses
     – Lisinopril 10-40mg once daily
     – Perindopril 2-8mg daily
     – Ramipril 1.25-10mg once daily

 • Side Effects:
     – Can produce serious first-dose hypotension
     – Cough, due to accumulation of bradykinin
     – Hyperkalaemia, due to inhibition of aldosterone release


                                                            46
3) Antihypertensive Drugs (Cont’d)

   • Angiotensin II receptor blockers (ARBs)

      – Compete with angiotensin II for tissue binding
        sites & prevent angiotensin II from combining with
        its receptors in body tissues
      – Used for hypertension, may be used as an
        alternative to ACE inhibitors in the management
        of heart failure and diabetic nephropathy.

          » Irbesartan 150-300mg once daily
          » Losartan 25-100mg once daily
          » Valsartan 80-160mg once daily


                                                        47
3) Antihypertensive Drugs (Cont’d)

   • Side-effects
       – Hypotension
       – Less likely to cause cough and hyperkalaemia
         than ACE inhibitors




                                                        48
 3) Antihypertensive Drugs (Cont’d)

• Nursing Alerts
Potential Adverse              Nursing Actions
Effects
 ACE inhbitors and             Instruct the patient to lie
 Angiotensin II receptor       down if hypotension develops
 antagonists may cause first
 dose hypotension
ACE inhibitors may produce     Warn patients about the
cough                          possibility of cough. Consult
                               the doctor if the cough is
                               bothersome to the patient

                                                           49
   3) Antihypertensive Drugs (Cont’d)

     Nursing Alerts (cont’d)
Potential Adverse Effects Nursing Actions


ACE inhibitors may cause         Avoid potassium supplements,
hyperkalaemia                    potassium containing salt
                                 substitutes and potassium-
                                 sparing diuretics
ACE inhibitors and Angiotensin   Avoid these dugs in pregnancy
II receptor antagonists are
contra-indicated in pregnancy

                                                                 50
         4) Antianginal Drugs
• Organic Nitrates
   – Used to treat or prevent angina
   – Mechanism:
       Nitrates are converted to NO in vascular
        smooth muscle
       NO activates guanylate cyclase
       Increase formation of cGMP so that the
        intracellular calcium levels decrease
       Vasodilation




                                                   51
     4) Antianginal Drugs(Cont’d)

– Relieves anginal pain by relaxing smooth muscles in the blood
  vessels (vasodilation) by several mechanisms
   • Dilate veins
   • Dilate coronary arteries
   • Dilate arterioles




                                                            52
4) Antianginal Drugs (Cont’d)

– Most widely used nitrate is nitroglycerin
  (Glyceryl trinitrate)
     Since it is highly lipid soluble, it can be
      administered by sublingual and transdermal
      route, as well as oral and intravenous routes




                                                      53
       4) Antianginal Drugs (Cont’d)

  • Nitrate preparations and dosage
Drug and dosage     Route        Dosage
form
Glyceryl Trinitrate
Sublingual tablet   Sublingual   1 tablet under the
500mcg                           tongue immediately
                                 as required
Spray 0.4mg/dose    Sublingual   Spray 1-2 doses
                                 under tongue

Capsule 2.5mg       Oral         1-2 capsules 2-3
(Retard)                         times a day        54
        4) Antianginal Drugs (Cont’d)

Drug and dosage        Route         Dosage
form

Glyceryl Trinitrate (Cont’d)
Transdermal            Transdermal   1 patch every 24
patches 5mg / 10mg                   hours
Isosorbide Mononitrate
Tablet 20mg            Oral          20mg bd to tid /
                                     40mg bd
Tablet 60mg            Oral          30-120mg in the
(controlled release)                 morning
Capsule 50mg           Oral          1-2 capsules in the
(sustained release)                  morning           55
       4) Antianginal Drugs (Cont’d)


Drug and dosage       Route   Dosage
form

Isosorbide Dinitrate
Tablet 10mg           Oral    30-240mg in divided
                              doses

Tablet 40mg           Oral    20-40mg every 12
(sustained release)           hours

Capsule 20mg          Oral    1 capsule bd or tid
(sustained release)
                                                    56
    4) Antianginal Drugs (Cont’d)

– Tolerance
   • Tolerance to nitrate induced vasodilation can
     develop rapidly
   • This may be due to depletion of sulfhydryl (S-H)
     groups in the vascular smooth muscle. These groups
     are needed to convert nitrate to NO




                                                          57
 4) Antianginal Drugs (Cont’d)

– Adverse Effects
   • Headache
   • Orthostatic hypotension
      – Symptoms include light headedness and
        dizziness
   • Reflex tachycardia




                                                58
        4) Antianginal Drugs (Cont’d)
        • Nursing Alerts:

Potential Adverse Effects Nursing Actions
Headache                    Inform patients that headache will
                            diminish with continued drug use. Can
                            be relieved by mild analgesics
Orthostatic hypotension     Slowly change from a sitting or lying
                            position to an upright position. Advise
                            the patient to lie or sit down if
                            symptoms of hypotension (eg.
                            dizziness, lightheadedness) occur
Tolerance                   To prevent tolerance, use the
                            minimum effective dose. For long-
                            acting preparations, they should be
                            used on an intermittent schedule to
                                                             59
                            allow at least 8 drug-free hours
     5) Antiarrhythmic Drugs
• Antiarrhythmic drugs are primary used to treat
  cardiac arrhythmias, which is a disturbance or
  irregularity in the heart rate, rhythm, or both
• Antiarrhythmic drugs are divided into 4 classes




                                                    60
     5) Antiarrhythmic Drugs (Cont’d)
• (i) Class I
   – Sodium channel blockers
   – Have a membrance-stablizing or anaesthetic effect on the
      cell of the myocardium
   – Are subdivided into I-A, I-B, I-C
        • I-A:
        • Quinidine
            – 200-400 mg tid or qid po
        • Procainamide
            – 25-50 mg/min slow iv injection; max:1g daily



                                                                61
5) Antiarrhythmic Drugs (Cont’d)
     • I-B:
     • Lidocaine
         – 50- 100 mg single bolus injection; followed
           by 1-4 mg/min infusion
     • I-C:
     • Flecainide
         – 100 mg bd po; max: 400 mg daily
     • Propafenone
         – 150-300 mg tid po




                                                         62
5) Antiarrhythmic Drugs (Cont’d)
   – Side effects of Class I:
     • Nausea, vomiting
     • Dizziness
     • Visual disturbances
     • Pro-arrhythmic effect
     • Heart block




                                   63
     5) Antiarrhythmic Drugs (Cont’d)
• (II) Class II
   – Beta Blockers
   – Block sympathetic stimulation of beta receptors in the heart
     & decrease the heart rate
       • Propranolol
           – 10-40 mg tid or qid po
       • Acebutolol
           – 400-1200 mg daily po in 2 to 3 divided dose
       • Esmolol
           – 50-200 mcg/kg/min IV infusion




                                                              64
5) Antiarrhythmic Drugs (Cont’d)
   – Side effects of Class II:
      • Nausea
      • Headache
      • Hypotension
      • Dizziness




                                   65
   5) Antiarrhythmic Drugs (Cont’d)

• (III) Class III
   – Potassium channel blocker
   – Prolong duration of action potential, slow repolarization,
     and prolong the refractory period in both atria and
     ventricles
       • Amiodarone
           – 200 mg one to three times daily po
       • Bretylium
           – 5-10 mg/kg IV infusion over 15-30 min q6-8h




                                                                  66
5) Antiarrhythmic Drugs (Cont’d)

   • Sotalol
      – Has combined Class II & Class III effects
      – A beta blocker that also delays repolarization
      – 160-320 mg po daily in 2 divided dose

– Side effects of Class III:
   • Proarrhythmias (Amiodarone & Sotalol)
   • Hypotension (Bretylium & Sotalol)
   • Malaise, fatigue & tremor (Amiodarone)



                                                         67
    5) Antiarrhythmic Drugs (Cont’d)
• Class IV:
   – Calcium Channel Blockers (CCB)
   – Block the movement of Ca into conductile & contractile
     myocardial cells
   – Verapamil & Diltiazem are the only approved CCB in
     arrhythmias

       • Verapamil
          – 40-120 mg tid po




                                                              68
 5) Antiarrhythmic Drugs (Cont’d)

   • Diltiazem
       – 0.25 mg/kg IV injection over 2 min, second bolus of
         0.35 mg/kg if needed; followed by 5-15 mg/hr
         continuous IV infusion if necessary

– Side effects of Class IV:
   • Proarrhythmias (Verapamil)
   • Heart block
   • Hypotension, headache, dizziness, constipation




                                                               69
    5) Antiarrhythmic Drugs (Cont’d)

• Nursing Alerts
  – Antiarrhythmic drugs are capable of causing new
    arrhythmias, as well as an exacerbation of existing
    arrhythmias
  – Older adults taking antiarrhythmic drugs are at
    greater risk for adverse reactions such as
    development of additional arrhythmias or
    aggravating of existing arrhythmias, hypotension,
    and congestive heart failure. Careful monitoring is
    necessary for early identification and management
    of adverse effects
                                                          70
          6) Drugs used for Dyslipidemia


• Used in the management of elevated blood lipids, which is a
  major risk factor for atherosclerosis and vascular disorders
  such as coronary artery disease and strokes




                                                                 71
6) Drugs used for Dyslipidemia (Cont’d)
    • (i) HMG CoA reductase inhibitors (Statins)
       – Inhibits HMG CoA reductase, the rate-limiting
          enzyme in cholesterol synthesis
       – Increase LDL receptors in hepatocytes
           • This enables hepatocytes to remove more LDLs
             from the blood
       – Also decrease VLDL levels and increase HDL levels




                                                         72
    6) Drugs used for Dyslipidemia (Cont’d)

Drug          Usual Dosage                 Comments

Atorvastatin 10-80mg taken at anytime      Take with or without
                                           food

Fluvastatin   20-40mg daily in the evening, Take with or without
              up to 40mg twice daily        food

Pravastatin   10-40mg at night             Take with food to
                                           reduce dyspepsia

Simvastatin   5-80mg at night              Take with food to
                                           reduce dyspepsia
                                                                   73
6) Drugs used for Dyslipidemia (Cont’d)

  – Adverse Effects
     • Headache, GI side effects (e.g. abdominal pain,
       flatulence, diarrhoea, nausea and
       vomiting)
     • Hepatoxicity
     • Myopathy




                                                         74
6) Drugs used for Dyslipidemia (Cont’d)
   • (ii) Fibric acid derivatives (Fibrates)
      – Increase oxidation of fatty acids in liver and
          muscle tissue, decrease hepatic production of
          triglycerides, decrease VLDL cholesterol and
          increase HDL cholesterol
      – Main indication is hypertriglceridemia (high plasma
          triglycerides)




                                                          75
6) Drugs used for Dyslipidemia (Cont’d)



Drug and dosage form   Usual Dosage

Clofibrate
capsule 500mg          2g daily in 2-4 divided doses

Fenofibrate
Capsule 100mg          3 capsules daily in the course
                       of main meals
Capsule (Micronized    1 capsule daily
fenofibrate) 200mg
                                                  76
6) Drugs used for Dyslipidemia (Cont’d)


 Drug and dosage form   Usual Dosage

 Gemfibrozil
 Capsule 300mg          1.2g daily in 2 divided doses
                        Usual range 0.9-1.5g daily

 Tablet 600mg




                                                        77
6) Drugs used for Dyslipidemia (Cont’d)
      – Adverse Effects
         • Nausea, vomiting and GI upset
         • Cholelithiasis (stones in the gall bladder) and
           cholecystitis (inflammation of the gallbladder)
         • Myopathy




                                                             78
6) Drugs used for Dyslipidemia (Cont’d)
  • (iii) Bile acid sequestrants
     – Bind bile acids in the intestinal lumen. This causes
         the bile acids to be excreted in faeces and
         prevents them being re-circulated to the liver
     – Mainly used as an adjunct to Statins to decrease
         LDL cholesterol levels




                                                              79
6) Drugs used for Dyslipidemia (Cont’d)
      – Cholestyramine
         • Usual dosage
             – 12-24g daily in water in one to four divided
               doses; Max: 36g daily
         • Adverse effects
             – Constipation, diarrhoea, nausea, vomiting,
               gastro-intestinal discomfort
             – Decreased absorption of fat-soluble
               vitamins




                                                              80
6) Drugs used for Dyslipidemia (Cont’d)
  • (iv) Nicotinic acid
     – Inhibits mobilization of free fatty acids from
        peripheral tissues, thereby reducing hepatic
        synthesis of triglycerides and secretion of VLDL,
        which leads to decreased production of of LDL
        cholesterol
     – Besides reducing LDL and VLDL levels, also
        effective in increasing HDL levels




                                                            81
6) Drugs used for Dyslipidemia (Cont’d)
      – Normal dose
         • 1-2g three times daily
      – Adverse effects
         • Flushing, itching, nausea, vomiting, diarrhoea
         • Hepatotoxic
         • Hyperglycaemia and hyperuricaemia




                                                            82
6) Drugs used for Dyslipidemia (Cont’d)

  • Nursing alerts:
 Potential Adverse    Nursing Actions
 Effects
 Statins
 Hepatotoxicity       Liver function should be
                      monitored during therapy

 Myopathy             Inform patient about the risk
                      of myopathy. Instruct them to
                      notify physician if unexplained
                      muscle pain or tenderness
                      occurs
                                                  83
      6) Drugs used for Dyslipidemia (Cont’d)

Potential Adverse Effects   Nursing Actions
Fibrates
Gallstones                  Inform patients about symptoms of
                            gallbladder disease (e.g. upper
                            abdominal discomfort, intolerance
                            of fried foods, bloating) and
                            instruct them to notify the
                            physician if these develop
Myopathy                    Warn patient to report any signs of
                            muscle injury, such as tenderness,
                            weakness, or unusual muscle pain

Liver Disease               Obtain periodic tests of liver
                            function                         84
   6) Drugs used for Dyslipidemia (Cont’d)


Potential Adverse        Nursing Actions
Effects
Bile acid sequestrants
Constipation             Inform patients that
                         constipation can be minimized by
                         increasing dietary fiber and
                         fluids. A mild laxative may be
                         used if needed.
Vitamin deficiency       Absorption of fat-soluble
                         vitamins (A, D, E, K) may be
                         impaired. Vitamin supplements
                         may be required
                                                         85
      6) Drugs used for Dyslipidemia (Cont’d)


Potential Adverse Effects   Nursing Actions
Nicotinic acid
Flushing                    Contact physician if the patient
                            experiences flushing (face, neck,
                            ears)
Hepatotoxicity              Monitor liver function during
                            treatment
Hyperglycaemia              Blood glucose should be monitored
                            frequently
Hyperuricaemia              Exercise caution in patients with
                            gout                              86
88

				
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